Modeling of transient luminous events in Earth middle atmosphere with apokamp discharge
V.F. Tarasenkoa aInstitute of High-Current Electronics, Siberian Branch of the Russian Academy of Sciences, Akademicheskii prosp. 4, Tomsk, 634055, Russian Federation bJoint Institute for High Temperatures, Russian Academy of Sciences, ul. Izhorskaya 13/19, Moscow, 127412, Russian Federation cInstitute for High Temperatures, Joint Institute for High Temperatures, Russian Academy of Sciences, ul. Izhorskaya 13/19, Moscow, 127412, Russian Federation
The phenomenon of the formation of an extended luminous structure at the bend of the channel of a high-voltage pulse discharge is discovered. It is called apokamp (from the Greek words απó — "from" and καμπν — "bend"), and the discharge as a whole is apokampic. In the course of experimental and theoretical studies, it is shown that the apokampic discharge is a narrow streamer channel that propagates at a characteristic speed of tens and hundreds of km/s, depending on the applied voltage, pressure, and gas type. The necessary conditions for apokamp formation are created in a relatively weak macroscopic electric field. The channel bend provides local field amplification that sets the starting orientation of the sprouting streamer channel. The frequency-pulse discharge power mode reproduces the streamer channel in each pulse, but the preceding ion-ion plasma backbone ensures that the channel shape is reproduced from pulse to pulse. The apokamp discharge is used for laboratory studies of conditions for the formation of blue jets and red sprites ‒ large-scale transient luminous events (transients) observed in the Earth's atmosphere at altitudes of tens of kilometers and formed naturally over areas with thunderstorm activity. The following six indicators of similarity apokamp and blue jets have been revealed: 1) their fronts move with approximately equal speeds; 2) they have similar range and structure of the maximum of luminescence spectra; 3) they are formed under similar conditions of pressure, composition of gas environment; 4) their formation requires to obtain plasma formation with excess positive charge relative to the Earth and the presence of a negatively charged zone above it; 5) they have similar morphology (composed of bone and plume); 6) they are formed including the Hz frequency range. The proposed experimental setup can also be used for meaningful testing of various hypotheses about the conditions of formation of transients of middle atmosphere and transients that occur in the atmospheres of other planets.
Keywords: apokamp, apokamp discharge, blue jets, middle atmosphere of Earth, transient luminous events red sprites PACS:52.80.Mg, 52.90.+z, 92.60.Pw, 07.05.Tp (all) DOI:10.3367/UFNe.2020.03.038735 Citation: Sosnin E A, Babaeva N Yu, Kozyrev A V, Kozhevnikov V Yu, Naidis G V, Skakun V S, Panarin V A, Tarasenko V F "Modeling of transient luminous events in Earth middle atmosphere with apokamp discharge" Phys. Usp., accepted
Received: 3rd, February 2020, revised: 2nd, March 2020, accepted: 12th, March 2020